Hey there, I'm no expert since I just started with all this, but I had the EXACT problems you are having. Unfortunately, before I figured it out my video card decided to go bonkers.
If I'm not mistaken, and I very well may be, you have to into 'custom resolutions', add a 'user defined' 856x480 resolution, reboot, then come back and fine tune in 'advanced timings' to Li On's values.
Oh, and you have to click something in pstrip to have it reload your settings upon startup.
See my other thread for my woes.
Good luck.